Damper access assembly, clamp assembly, and clamp member

ABSTRACT

A clamp assembly is provided for use in a duct system. The clamp assembly includes a clamp member including a base portion and first and second lateral portions. The first and second lateral portions extend less than the full circumferential length of the base portion. The clamp assembly may include a first member, a second member, and a hinge operatively coupling the first member to the second member. A damper access assembly includes an adapter, a damper access duct section, and an annular clamp member. A first flange of the adapter and a second flange of the duct section are configured to form a generally T-shaped joint between the adapter and the damper access duct section. The clamp member is configured to removably secure the adapter to the damper access duct section. The damper access duct section is configured to be removable relative to the damper enclosure and the ductwork.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation of U.S. patent application Ser. No.13/708,287, filed Dec. 7, 2012 (now U.S. Pat. No. 9,551,505), which is acontinuation-in-part application of U.S. patent application Ser. No.13/488,881, filed Jun. 5, 2012 (now U.S. Pat. No. 9,341,291), thedisclosures of which are hereby incorporated by reference herein intheir entirety. This application is related to U.S. Design applicationSer. No. 29/439,187, filed Dec. 7, 2012 (now U.S. Design Pat. No.D737,133) and U.S. Design application Ser. No. 29/439,188, filed Dec. 7,2012 (now U.S. Design Pat. No. D736,072), the disclosures of which arehereby incorporated by reference herein in their entirety.

FIELD OF THE INVENTION

The present invention relates generally to ventilation duct systems and,more particularly, to access assemblies, clamp assemblies, and clampmembers for use in a ventilation duct system to provide access to adamper.

BACKGROUND OF THE INVENTION

In ventilation duct systems, there are oftentimes a variety ofcomponents connected to the duct system that must be periodicallyinspected, maintained, and repaired, as necessary. Due to their internalconstruction, however, these components are typically not easilyaccessible for routine inspection, maintenance, and repair.

One such internal device is a damper. As is known, a damper includes oneor more movable plates, blades, or curtains that control the flow of afluid, usually air, in the duct system. Like many mechanical devices,dampers require preventive maintenance and, in the event of operationalfailure, replacement or repair. As one particular example, fire dampersare safety devices that are often found in walls or floors of a buildingand are designed to prevent the rapid spread of flames and hot gasesthrough the building via the ventilation duct system. Fire dampersinclude a fusible link that, when exposed to excessive heat, causes thedamper to abruptly close. The action closes the duct system so that itdoes not provide an avenue for the spread of fire through the building.

Because some dampers, such as fire dampers, are safety devices, theymust be protected from collateral damage to the ductwork so that theymaintain their operational effectiveness in the event of an emergency.For example, because fire dampers are designed to prevent the spread offire through the ductwork in a building, the ductwork operativelycoupled to the damper is designed to break away without damage to thedamper itself. In this manner, should part of the building collapseadjacent the damper and dislodge or destroy the ductwork leading up tothe damper, the ductwork may cleanly separate from the damper so thatthe integrity of the damper is maintained. Thus, structural failuresthat are typically associated with a fire may not defeat the purpose ofthe damper and thereby cause catastrophic or rampant spread of firethrough the ductwork.

Normally, access to the fire damper and the link are provided by a smallaccess door in the duct that is located in proximity to the damper.However, these doors, due to their location and orientation on theductwork and/or proximity to other components of the duct system orother structures in the building, often provide only limited visibilityof the fire damper and link and thus make inspection, maintenance, andrepair awkward and difficult. In addition, replacement of the damperand/or the link is often not possible via the access door so that theirreplacement is a time-consuming and expensive endeavor. Often,replacement in this situation may essentially require dismantling of alarge portion of the duct system simply to gain physical access to thefire damper.

Thus, there is a need for improved access to dampers that overcome theseand other shortcomings and drawbacks of known access doors inventilation duct systems.

SUMMARY OF THE INVENTION

The present invention overcomes the foregoing and other shortcomings anddrawbacks of access doors heretofore known for use in ventilation ductsystems. While the invention will be described in connection withcertain embodiments, it will be understood that the invention is notlimited to these embodiments. On the contrary, the invention includesall alternatives, modifications and equivalents as may be includedwithin the spirit and scope of the present invention.

In accordance with the principles of the present invention, a clampassembly is provided for use in a ventilation duct system for joining afirst outwardly directed flange of a first duct with a second outwardlydirected flange of a second duct. The outwardly directed flanges areconfigured to confront one another and define a gap therebetween.

According to one aspect of the present invention, the clamp assemblyincludes an annular clamp member including a base portion that definesan annular periphery of the clamp member. A first lateral portion and asecond lateral portion each extend from the base portion. The firstlateral portion confronts the second lateral portion to define a channeltherebetween for receiving the first and second flanges. The firstlateral portion and second lateral portion extend less than the fullcircumferential length of the base portion.

According to one aspect of the present invention, the first lateralportion of the clamp assembly includes a plurality of circumferentiallyspaced-apart first lateral portions and the second lateral portionincludes a plurality of circumferentially spaced-apart second lateralportions.

According to another aspect of the present invention, each of the firstoutwardly directed flange and the second outwardly directed flangeincludes a leg extending transversely therefrom. The transverse legs areconfigured to form a generally T-shaped joint when the first flangeconfronts the second flange. The channel of the annular member isconfigured to receive the T-shaped joint therein.

According to another aspect of the present invention, the clamp assemblyfurther includes at least one faceplate configured to be secured to oneof the first duct section or the second duct section. The faceplateincludes a first leg configured to be secured to the duct section and asecond leg. The clamp member is configured to receive the second legtherein.

According to another aspect of the present invention there is a clampassembly for joining a first outwardly directed flange of a first ductwith a second outwardly directed flange of a second duct. The flangesare configured to confront one another and define a gap therebetween.The assembly includes a first member, a second member, and a hingeoperatively coupling the first clamp member to the second clamp memberto form at least a portion of an annular clamp member. The first memberis moveable relative to the second member by the hinge between an openedposition in which the clamp member is installable onto the first andsecond ducts and a closed position in which the assembly engages each ofthe first and second flanges. Each of the first and second membersincludes a base portion and a first lateral portion and a second lateralportion each extending from the base portion. The first lateral portionconfronts the second lateral portion to define a channel therebetweenfor receiving the first and second flanges.

According to another aspect of the present invention there is a damperaccess assembly for use in a ventilation duct system. The ventilationduct system includes ductwork and a damper enclosure configured toenclose a damper and having an inlet and an outlet operatively coupledto the ductwork. The damper access assembly includes an adapter, adamper access duct section, and an annular clamp member. The adapterdefines a passage therethrough and has a first end and a second end. Thefirst end is configured to be operatively coupled to one of the inlet oroutlet of the damper enclosure, and the second end includes a firstradially outwardly directed flange including a leg extending at atransverse angle therefrom.

The damper access duct section defines a passage therethrough and has afirst end and a second end. Each of the first end and the second end ofthe damper access duct section includes a second radially outwardlydirected flange at the respective first end and second end thereof. Eachof the second flanges include a leg extending at a transverse angletherefrom. The first flange of the adapter and one of the second flangesof the duct section are configured to form a generally T-shaped jointbetween the adapter and the damper access duct section.

The annular clamp member includes a base portion that defines an annularperiphery of the clamp member and a first lateral portion and a secondlateral portion that each extend from the base portion. The firstlateral portion and the second lateral portion extend less than the fullcircumferential length of the base portion. The first lateral portionconfronts the second lateral portion to define a channel therebetweenfor receiving the generally T-shaped joint to releasably couple thedamper access duct section to the adapter.

The first flange of the adapter is configured to be operatively andreleasably coupled to one of the second flanges of the damper accessduct section at one of the first or second ends thereof. The othersecond flange at the other of the first or second end of the damperaccess duct section is configured to be operatively and releasablycoupled to the ductwork so that the damper access duct section isremovable relative to the damper enclosure and the ductwork to permitaccess to the damper when the damper access duct section is removed.

According to another aspect of the present invention, there is anannular clamp member including a first member, a second member, and ahinge operatively coupling the first member to the second member. Thefirst member is moveable relative to the second member by the hingebetween an opened position in which the clamp member is installable ontothe first and second flanges and a closed position in which the annularclamp member engages each of the first and second flanges to releasablycouple the access duct section to the adapter. Each of the first andsecond members includes a base portion defining an annular periphery ofthe clamp member and includes a first lateral portion and a secondlateral portion each extending from the base portion. The first lateralportion confronts the second lateral portion to define a channeltherebetween for receiving the generally T-shaped joint. The damperaccess duct section is configured to be operatively and releasablycoupled to the ductwork with the annular clamp member so that the damperaccess duct section is removable relative to the damper enclosure andthe ductwork to permit access to the damper when the damper access ductsection is removed.

The above and other objectives and advantages of the present inventionshall be made apparent from the accompanying drawings and thedescription thereof.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of this specification, illustrate an embodiment of the inventionand, together with the general description of the invention given aboveand the detailed description of embodiments given below, serve toexplain the principles of the present invention.

FIG. 1 is a partial cross-sectional side elevational view of anexemplary ventilation duct system according to one embodiment of thepresent invention;

FIG. 2 is a perspective view of a portion of the ventilation duct systemof FIG. 1 according to one embodiment of the present invention;

FIG. 3 is an exploded perspective view of the embodiment shown in FIG.2;

FIG. 4 is a cross-sectional view of the embodiment shown in FIG. 2 takenalong section line 4-4;

FIG. 5A is an enlarged view of the encircled area 5A of FIG. 4illustrating one embodiment of a joint;

FIG. 5B is an enlarged view of the encircled area 5A of FIG. 4illustrating an alternative embodiment of the joint to that shown inFIG. 5A;

FIG. 6A is a cross-sectional view taken along section line 4-4 of FIG. 2depicting a breakaway feature of one embodiment of the invention;

FIG. 6B is a cross-sectional view taken along section line 4-4 of FIG. 2similar to that of FIG. 6A depicting another breakaway feature of oneembodiment of the invention;

FIG. 7 is a partially disassembled perspective view of the embodiment ofthe invention shown in FIG. 2;

FIG. 8 is a partial cross-sectional plan view of another embodiment ofthe invention;

FIG. 8A is an enlarged view of the encircled area 8A in FIG. 8;

FIG. 9 is a partial cross-sectional plan view of another embodiment ofthe invention;

FIG. 10 is a partial cross-sectional plan view of another embodiment ofthe invention;

FIG. 10A is an enlarged view of the encircled area 10A in FIG. 10;

FIG. 11 is a perspective view of another embodiment of the invention;

FIG. 12 is an exploded perspective view of the embodiment shown in FIG.11;

FIG. 13A is a perspective view of one embodiment of a clamp according tothe invention;

FIG. 13B is a perspective view of one embodiment of a clamp according tothe invention;

FIG. 14A is a perspective view of one embodiment of a clamp according tothe invention;

FIG. 14B is a perspective view of one embodiment of a clamp according tothe invention;

FIG. 14C is a perspective view of one embodiment of a clamp according tothe invention;

FIG. 15 is a cross-sectional view taken along section line 15-15 of FIG.11 of a joint formed with the clamp of FIG. 13A according to oneembodiment of the invention;

FIG. 16A is a cross-sectional view taken along section line 16-16 ofFIG. 11 of a joint formed with the clamp of FIG. 13A according toanother embodiment of the invention;

FIG. 16B is a cross-sectional view taken along section line 16-16 ofFIG. 11 of a joint formed with the clamp of FIG. 13A according toanother embodiment of the invention;

FIGS. 17A and 17B are cross-sectional views of other jointconfigurations taken along section line 16-16 of FIG. 11 according toembodiments of the invention;

FIG. 17C is a cross-sectional view taken along section line 15-15 ofFIG. 11 of a joint formed according to another embodiment of theinvention;

FIGS. 17D, 17E, and 17F are cross-sectional views of other jointconfigurations taken along section line 16-16 of FIG. 11 according toembodiments of the invention;

FIG. 18 is a cross-sectional view of a joint formed according to oneembodiment of the invention;

FIG. 19 is a cross-sectional view of a joint formed according to oneembodiment of the invention;

FIG. 20A is a disassembled perspective view of one embodiment of theinvention;

FIG. 20B is a cross-sectional view taken along section line 20B-20B ofFIG. 20A following assembly;

FIG. 21A is a disassembled perspective view of one embodiment of theinvention; and

FIG. 21B is a cross-sectional view taken along section line 21B-21B ofFIG. 21A following assembly.

DETAILED DESCRIPTION OF THE INVENTION

Referring now to the figures, and to FIG. 1 in particular, an exemplaryventilation duct system 10 is shown in accordance with the principles ofthe present invention. The duct system 10 may include ductwork ofvarious types of duct components, such as, multiple ventilation ductruns 12 and an elbow 14. The duct system 10 further includes a damperassembly 16 and a damper access assembly 18, each described in moredetail below, which are interconnected at joints to form the duct system10. The duct system 10 may be configured to direct the flow of a fluid,for example, air, to various parts of a building.

For example, the duct system 10 may form one branch of a heating,ventilation, and air conditioning (HVAC) system in a building. While theexemplary ventilation duct system 10 is shown including specificductwork, it will be appreciated that other types and configurations ofductwork are also known to those of ordinary skill in the art and arealso possible without departing from the spirit and scope of the presentinvention. For example, although not shown, the ductwork may include oneor more sleeve couplings to couple adjacent ducts 12 together as well asone or more duct reducers to couple ducts of different cross-sectionaldimensions together.

As will be described in greater detail below, all or a portion of thedamper access assembly 18 may be easily removed from the duct system 10thereby permitting visual and/or physical access to internal componentsof the duct system 10. For example, the damper access assembly 18 mayallow access to the internal components of the damper assembly 16 thatare not generally assessable through an access door (not shown).

To that end, and with continued reference to FIG. 1, the damper assembly16 may include a damper 22 secured within an enclosure 24. Further, thedamper 22 may include a plurality of blades 26 mounted within a frame28. The blades 26 may be oriented or controlled to regulate the flow offluid through the damper assembly 16. The frame 28 may be secured to theenclosure 24. The enclosure 24 may include one or more sidewalls 25 andopposing end walls 27 extending transversely from the sidewall 25. Wheninstalled, the enclosure 24 may be secured to the structure of thebuilding, such as to a wall 30, by retaining angles 32 between thesidewall 25 and the wall 30 so as to align the damper 22 with the wall30, as shown. However, embodiments of the present invention are notlimited to the relative orientation or position of the damper 22relative to the building structure. For example, the damper 22 may beoffset from the wall 30. This may be the case for smoke dampers whichmay be installed at or adjacent to the point where the duct passesthrough a smoke barrier (not shown).

The damper assembly 16 may include an inlet 34 and an outlet 36operatively coupled to the ductwork. In the exemplary embodiment shownin FIG. 1, the inlet 34 and the outlet 36 are each defined by theendwalls 27. With this construction, the damper assembly 16 may operateto throttle or regulate a flow of a fluid (indicated by arrow 38)between the inlet 34 and the outlet 36. By way of example only, thefluid may be air or other gases. Embodiments of the present inventionare not, however, limited to any specific fluid. While the inlet 34 andthe outlet 36 are shown and described in a particular orientation shownin FIG. 1, this orientation is merely exemplary. It will be appreciatedthat the inlet 34 and the outlet 36 may be reversed from that shown.Furthermore, the flow of fluid through the damper assembly 16 may bereversed during use of the duct system 10. As such, embodiments of thepresent invention are not limited to the specific direction of the flowof fluid as indicated in FIG. 1.

In this exemplary configuration, removal of all or a portion of thedamper access assembly 18 may permit a technician to visually inspect,maintain, and repair components found in the enclosure 24, such as thedamper 22. In this regard, the damper 22 may be any one type of avariety of types of dampers including, by way of example only, a firedamper, a balancing damper, a control damper, a fire smoke damper, abackdraft damper, or a smoke damper, to name only a few. As such, thedamper assembly 16 may further include additional components. Forexample, when the damper 22 is a fire damper, and with reference to FIG.1, the damper assembly 16 may further include a fusible link 40 and astrap 42. As is known, exposing the fusible link 40 to sufficient heatwill cause the strap 42 to release the blades 26. Gravity or a springextends the blades 26 across the frame 28 to close off the inlet 34 fromthe outlet 36 to prevent or at least inhibit the spread of a firethrough the wall 30. Though not shown, dampers may further includesprings, guide tracks, and other components depending on the type andfunction of the damper. Advantageously, removal of a portion of thedamper access assembly 18 then provides an avenue for inspection,maintenance, and/or repair of various components located internal to thedamper assembly 16.

Furthermore, while the damper assembly 16 is shown to include avertically oriented damper, it will be appreciated that embodiments ofthe present invention are not limited to ventilation duct systems havingvertically oriented dampers. In this regard, horizontal style dampersare known and are often used in floors or in other locations thatrequire a horizontal orientation. Embodiments of the present inventionallow inspection, maintenance, and repair of horizontal dampers andother components that are internally located in the duct system 10.

As described above, and with reference to FIGS. 1-3, the damper accessassembly 18 allows a technician to easily access these and otherinternal components. To that end, and in one embodiment, the damperaccess assembly 18 includes a damper access duct section 44 and anadapter 46. In the installed position, as shown in FIGS. 1 and 2, thedamper access assembly 18 may be operatively coupled to the damperassembly 16 at one end thereof and to the duct 12 at the other endthereof.

In particular, in the embodiment shown, one end of the damper accessduct section 44 is operatively coupled to the duct 12, and the adapter46 is operatively coupled to the damper assembly 16 at the outlet 36 ofthe damper enclosure 24. As shown, the damper access duct section 44 maybe coupled to the duct 12 with a clamp 48 at one end thereof and may becoupled to the adapter 46 with a clamp 50 at the other end thereof. Asis described in more detail below, the damper access duct section 44 maybe disconnected from the duct system 10 by removing clamps 48 and 50 toallow the damper access duct section 44 to be removed relative to thedamper enclosure 24 and the ductwork, such as, the duct 12, to permitaccess to internal components found in the duct 12 and/or the damperassembly 16, such as the damper 22.

With reference to FIGS. 2, 3, and 4, in which like reference numeralsrefer to like features, the damper access duct section 44 has a sidewall52 that defines a passage 54 along an internal surface thereof. In theembodiment shown, the damper access duct section 44 has a tubularconfiguration and may have a cylindrical shape. It will be appreciated,however, that the damper access duct section 44 is not limited tocylindrical shapes as other cross-sectional shapes are contemplated, forexample, rectangular, square, or oval cross-sectional shapes. Thepassage 54 may be in direct contact with the fluid flow from the damperassembly 16. However, the damper access duct section 44 may include aliner (not shown), such as, internal insulation, along the internalsurface of the sidewall 52 so that the passage 54 is defined by theliner. Similarly, the external surface of the sidewall 52 may be coveredby an external liner (not shown), such as, external insulation.

The sidewall 52 has ends 56 and 58 each having a respective radiallyoutwardly directed flange 60, 62. In one embodiment, one or both of theradially outwardly directed flanges 60, 62 are integrally formed withthe sidewall 52. Integrally forming the flanges 60, 62 may be achievedby one or more of the methods disclosed in U.S. Pat. No. 7,997,112; U.S.Publication No. 2009/0083962; and U.S. Publication No. 2010/0038902,which are assigned to the assignee of the present invention and areincorporated by reference herein in their entireties. Alternatively, theflanges 60, 62 may be formed with a van stone machine, by way ofexample, or any other conventional method.

As described above, the adapter 46 is operatively coupled to the damperaccess duct section 44 and the damper assembly 16. In that regard, theadapter 46 includes a sidewall 64 that defines a passage 66. Thesidewall 64 has ends 68 and 70. At least one of the ends 68 and 70 has aradially outwardly directed flange 72. In one embodiment, the flange 72may be formed by one of the methods disclosed above with regard toforming one or both of the flanges 60, 62. In the embodiment shown, thedamper access duct section 44 has a tubular configuration and may have acylindrical shape. However, like the damper access duct section 44described above, it will be appreciated, that the adapter 46 is notlimited to cylindrical shapes as other cross-sectional shapes arecontemplated, for example, rectangular, square, or oval cross-sectionalshapes. Further, embodiments of the invention are not limited to theadapter 46 and the damper access duct section 44 having the same shape,as is described in detail below.

More specifically, as shown in FIGS. 3 and 4, at the joint between thedamper access duct section 44 and the adapter 46, the adapter 46 via theflange 72 may be operatively coupled to the damper access duct section44 via the flange 62. For example, the clamp 50 may engage each of theflanges 62 and 72 to force them toward one another so as to removablysecure the damper access duct section 44 to the adapter 46.

In one embodiment, and with reference to FIG. 5A, the flanges 62 and 72may align with one another in a direct abutting relationship. That is,when the damper access assembly 18 is in an installed position, anoutwardly facing surface of the flange 62 and an outwardly facingsurface of the flange 72 may be in contact with the one another. Theclamp 50 may be disposed over the flanges 62 and 72 so as to operativelycouple the damper access duct section 44 and the adapter 46 and preventunintentional separation thereof.

In this regard, the clamp 50 may include clamp legs 74 a, 74 b and aloop portion 76 formed between and joining clamp legs 74 a, 74 b. Theclamp 50 may also include a gasket member 78 positioned proximate theloop portion 76. The gasket member 78 may span across the interfacebetween the flange 62 and the flange 72 so as to inhibit or preventtravel of fluid through any gap that may exist between the flange 62 andthe flange 72 thereby forming a fluid-tight seal between the damperaccess duct section 44 and the adapter 46.

In an alternative embodiment of the clamp 50, shown in FIG. 5B, theflange 62 and the flange 72 are separated by a gasket member 78′ ratherthan the flange 62 and the flange 72 abutting one another. The clamp 50may then engage the opposing flanges 62 and 72 to operatively couple theadapter 46 and the damper access duct section 44 and preventunintentional separation thereof and to provide a fluid-tight sealtherebetween. Clamp 48 may be similar to clamp 50. Clamps, such asclamps 48 and 50 are disclosed in commonly owned U.S. Pat. No.7,997,112; U.S. Publication No. 2009/0083962; and U.S. Publication No.2010/0038902, as set forth above.

While the embodiments disclosed herein describe the clamp 50 as couplingthe damper access duct section 44 and the adapter 46 together, it willbe appreciated that other clamps capable of securing these componentstogether may be used in accordance with embodiments of the presentinvention disclosed herein. By way of example only, and not limitation,clamps 48 and 50 may be angle ring-type clamps with a fastenerconnecting opposing flanges, a drawband clamp, and a barrel clamp.

As introduced above, and with reference to FIGS. 3, 4, and 5A and 5B,the adapter 46 is operatively coupled to the damper assembly 16. In thisregard and in one embodiment, the damper assembly 16 includes a collar80, which may be a separate component attached to the enclosure 24, asshown, by bending metal tabs 83 around the edge 86 of the enclosure 24that defines the outlet 36 or may be integral to the enclosure 24.However, there are many ways by which the collar 80 may be attached tothe enclosure 24, for example, by welding or spot welding, andembodiments of the present invention are not limited to any particularmethod. The enclosure 24 may have sidewalls and end walls to more fullyenclose the damper 22.

In the embodiment shown, the collar 80 may include a sleeve coupling 82that extends generally perpendicular to the radially outwardly directedtab 83. The sleeve coupling 82 may further include a radially outwardlydirected annular bead 84 spaced apart from the tab 83 so as to provide arecess into which the edge 86 of the enclosure 24 may extend when thecollar 80 is attached to the enclosure 24.

As shown best in FIGS. 5A and 5B, the sleeve coupling 82 may furtherinclude a radiused bottom wall 88. The bottom wall 88 may have agenerally constant radius of curvature although other curved or arcuateshapes of the bottom wall 88 are also contemplated. A gasket 90 may bepositioned within and conform to the bottom wall 88. The gasket 90 maybe configured as a double lip seal including a pair of annular sealingflanges 92 a and 92 b (shown best in FIG. 6A). The sealing flanges 92 aand 92 b may extend radially outward to sealingly engage the adapter 46,such as along the passage 66, when the adapter 46 is positioned on thecollar 80 during installation of the damper access assembly 18. Thus,the flanges 92 a and 92 b may limit or restrict ingress or egress offluid between the adapter 46 and the collar 80. It will be appreciatedthat the gasket 90 shown is merely exemplary as the gasket 90 may haveany number of different configurations from that shown while forming afluid-tight seal between the collar 80 and the adapter 46. Embodimentsof the present invention are thus not limited to any particularconfiguration of the gasket. Exemplary gaskets suitable for use inembodiments of the present invention are disclosed in commonly ownedU.S. Pat. Nos. 7,523,964; D534,253; and D529,598, which are assigned tothe assignee of the present invention and are incorporated by referenceherein in their entireties. By way of example, other seal configurationsmay include a circular cross-sectional configuration and a multipleflange configuration, for example, similar to the flanges 92 a and 92 b,but three or more flanges. Furthermore, each flange in such aconfiguration may differ from the configuration of adjacent flanges. Inthis regard, each flange may be of different height or width. Theconfiguration may depend upon the application.

The adapter 46 may be slightly larger in size (e.g., larger in diameter)so that the passage 66 cooperates with the outer surface 94 of thecollar 80. In other words, the adapter 46 may slip over and surround thecollar 80 with the sealing flanges 92 a and 92 b engaging the passage66. The end 70 of the adapter 46 may then abut the annular bead 84 whenthe adapter 46 is fully seated on the collar 80, as shown. In thisregard, the annular bead 84 may operate as a stop for the adapter 46 andprovide a visual confirmation that the adapter 46 is properly installed.In the embodiment shown in FIGS. 4, 5A, and 5B, a fastener 98, such as asheet-metal screw, may pass through each of the adapter 46 and thecollar 80 to limit movement of the adapter 46 relative to the collar 80during normal operation of the duct system 10.

Advantageously, and with reference now to FIG. 6A, the slip-typeconnection between the adapter 46 and the collar 80, even if securedwith one or more fasteners 98, allows the damper access assembly 18 tobreak away from the collar 80 in an emergency situation. For example,breakaway of the damper access assembly 18 from the collar 80 may occurin the event that the ceiling (not shown) or another portion of thebuilding collapses onto a portion of the duct system 10 or onto thedamper access assembly 18. The application of this type of load to thedamper access assembly 18 is indicated by an arrow 110 in FIG. 6A. Thus,by way of example only, where the damper 22 is a fire damper,embodiments of the present invention may provide for a breakaway featureso that should the fire damper activate to contain a fire, the integrityof the fire damper in the wall 30 is maintained if a portion of a ductsystem 10 beyond the collar 80 collapses. The damper access assembly 18,in particular the adapter 46, may separate from the collar 80 in amanner that limits any damage to the damper assembly 16 and specificallyto the damper 22.

Similarly, and with reference to FIGS. 1 and 6B, in the embodiment inwhich the enclosure 24 includes sidewall 25 and end walls 27, the duct12 may be operatively coupled to the enclosure 24 by a slip-typeconnection similar to that described above between the adapter 46 andthe collar 80. As shown in FIG. 6B, a collar 130 extends from the endwall 27 that defines the inlet 34. The collar 130 may be similar to thecollar 80, described above, though embodiments of the present inventionare not limited thereto. A gasket 132 may be disposed on the collar 130to sealingly engage the duct 12 when the duct 12 is slid over the collar130. When operatively coupled thereto, duct 12 may be secured in placewith one or more fasteners 98 (shown in FIG. 1). Thus, the gasket 132may substantially prevent fluid leakage between the collar 130 and theduct 12 during normal operation of the duct system 10. However, theslip-type connection between the duct 12 and the collar 130 may allowthe duct 12 to break away from the collar 130 in the event that a partof the building structure collapses onto the duct 12. Thus, by way ofexample only, where the damper 22 is a fire damper, embodiments of thepresent invention may provide for a breakaway feature so that should thefire damper activate to contain a fire, the integrity of the fire damperin the wall 30 is maintained if a portion of a duct system 10 beyond thecollar 130 collapses. The duct 12 may separate from the collar 130 in amanner that limits any damage to the damper assembly 16 and specificallyto the damper 22.

In another embodiment of the invention, as shown in FIGS. 10 and 10A,the damper access assembly 18 includes an adapter 124 and the damperaccess duct section 44. The enclosure 24 may have an integral collarportion 126. In this regard, the enclosure 24 may be configured as aType C fire damper, as is known in the art. The adapter 124 may beconfigured to slide inside an integral collar 126 of the enclosure 24.The adapter 124 may be coupled to the integral collar 126 with afastener 98. Neither the collar 126 nor the adapter 124 may include agasket or seal, however, a liquid sealant may be used to form a fluidtight seal between the integral collar 126 and the adapter 124. It willbe appreciated that, alternatively, the adapter 124 may slide over theoutside of the integral collar 126. The joint connections between theadapter 124 and the damper access duct section 44 and between the damperaccess duct section 44 and the duct 12 may be similar to those asprovided above with regard to FIGS. 1-5B.

With reference now to FIGS. 2, 3, and 4, the damper access assembly 18may be coupled to the duct 12 at end 56. In particular, the flange 60may cooperate with a flange 100 on the duct 12. In this regard, theflange 100 may be integral with the duct 12, as shown, or may be aseparate annular ring of metal that may be secured to the duct 12 bywelding or with fasteners (not shown). Existing duct may therefore beretrofitted with the flange 100 where it is desired to provide anexisting duct system with the damper access assembly 18. Similar to thejoint between the damper access duct section 44 and the adapter 46, thejoint between the duct 12 and the damper access assembly 18 may includea direct abutting relationship between the flange 60 and the flange 100.The clamp 48 may then operatively couple the damper access duct section44 to the duct 12, or a gasket (not shown) may separate the flange 60from the flange 100 though the clamp 48 may operatively couple thedamper access duct section 44 to the duct 12. The clamp 48 may besimilar to the clamp 50, as shown in FIG. 5A or 5B, or may be adifferent clamp, such as those disclosed above.

With reference now to FIGS. 2 and 7, as described above, once the damperaccess duct section 44 is removed from between the duct 12 and theadapter 46, a technician may directly access internal components of theduct system 10. For example, removing the damper access duct section 44permits access to the damper 22 through the outlet 36 of the damperassembly 16. In contrast to access doors (not shown), which are oftenconstructed into a side of a duct system and may only provide an angledaccess to the damper 22, according to embodiments disclosed herein, thetechnician may access the damper 22 more directly along a longitudinalaxis 112, which may correspond to the longitudinal axis of the duct 12.Thus, in one embodiment, the duct system 10, as shown in FIG. 1, doesnot require an access door or panel. In addition, although not shown andnot required to gain access to the internal components of the damperassembly 16, the adapter 46 may also be slipped off of the collar 80.This may only require removal of the fasteners 98, as shown in FIG. 4,and pulling the adapter 46 in the direction of the duct 12 to slip theadapter 46 from the collar 80.

Specifically, in one embodiment and with reference to FIG. 7, to removethe damper access duct section 44 from the duct system 10, a technicianmay disengage the clamps 48 and 50 from the corresponding joints betweenthe damper access duct section 44 and the adapter 46 on the one end andbetween the damper access duct section 44 and the duct 12 at the otherend. In this regard, the clamp 48 may be disengaged from the flanges 60and 100 so that the damper access duct section 44 and the duct 12 may bemovable relative to one another at this joint. The technician may thendisengage the clamp 50 from the flanges 62 and 72 so that the damperaccess duct section 44 and the adapter 46 may be movable relative to oneanother at that joint. Removing each of the clamps 48 and 50 accordinglyreleases the damper access duct section 44 from the duct system 10. Thetechnician may therefore remove the damper access duct section 44 andset it aside for performing inspection, maintenance, and/or repair ofthe internal components of the damper assembly 16, such as the damper22. It will be appreciated that removal of the damper access ductsection 44 is achieved without bending, cutting, or other permanentdamage to the adapter 46 or the duct 12 so that each may be reused whenthe damper access duct section 44 is reattached thereto.

Once the inspection and/or maintenance of the internal components of thedamper assembly 16 is complete, the technician need only reposition thedamper access duct section 44 between the adapter 46 and the duct 12 toalign the flanges 60 and 100 and flanges 62 and 72. Once aligned, clamps48 and 50 may be brought into communication with the respective flangesand then reengaged to thereby operatively couple the damper access ductsection 44 to each of the duct 12 and the adapter 46.

With reference now to FIG. 8, in which like reference numerals refer tolike features in the figures, the damper enclosure 24 is a wall sleeve114. Unlike the damper enclosure 24 having sidewalls and endwalls, asshown in FIG. 2, for example, the damper enclosure of this embodiment inthe form of the wall sleeve 114 may be a tubular configuration, forexample, a rectangular configuration. In this embodiment, the wallsleeve 114 is secured to the wall 30 by the retaining angles 32. Thewall sleeve 114 thereby defines the inlet 34 and the outlet 36 in such amanner so that the inlet 34 and the outlet 36 are substantially the samecross-sectional area as the sleeve 114. It will be appreciated that bysuch a configuration the blades 26 and the frame 28 may extend directlyinto the flow of fluid within the sleeve 114. The damper access assembly18 may include the damper access duct section 44 and an adapter 116 thatmay be a rectangular-to-round coupler to operatively couple to therectangular-shaped outlet 36. The adapter 116 may be operatively coupledto the wall sleeve 114 by a breakaway connection 118. With reference toFIG. 8A, the breakaway connection 118 may be one of many duct-sleeveconnections as provided in UL555, sixth edition, including, for example,a plain “S” slip, a hemmed “S” slip, a double “S” slip, an inside slipjoint, and a standing S. At the other end of the damper access assembly18, the damper access duct section 44 may be coupled to around-to-rectangular portion 120 of the duct 12.

In another embodiment of the invention, as shown in FIG. 9, the damperaccess assembly 18 may include an adapter 122. The adapter 122 may beanother configuration of a rectangular-to-round coupler that cooperateswith a rectangular wall sleeve 114.

It will be appreciated that, in each of the embodiments shown in FIGS.8, 9, and 10, the damper access duct section 44 may be removed andreinserted in a manner similar to that described above with regard toFIG. 7.

As described above, the cross-sectional configuration of the damperaccess assembly may vary. By way of example, and with reference to FIG.11 in which like reference numerals refer to like features throughoutthe figures, a damper access assembly 140 is shown having a rectangularconfiguration. Such a configuration may be utilized, for example, wherethe duct system 10 (shown in FIG. 1) also has a rectangularconfiguration. Alternatively, it will be appreciated that around-to-rectangular adapter, such as that shown in FIG. 9, may beutilized to transition a duct system having a circular configuration toone that has a rectangular configuration. Further in this regard, therectangular configuration of the damper access assembly 140 shown inFIG. 11 may therefore be used in ducts having a generally circular crosssectional configuration.

In particular, as shown in FIG. 11, the damper access assembly 140 maybe installed in the duct system to permit visual and or physical accessto internal components of the duct system, as is set out above withregard to the damper access assembly 18 shown in FIG. 1. To these andother ends, the assembly 140 includes a damper access duct section 142and an adapter 144. In the installed position, as shown in FIG. 11, theassembly 140 may be operatively coupled to a damper assembly (notshown), such as the damper assembly 16 shown in FIG. 1, at one endthereof via the adapter 144 and to the duct 12 at the other end thereof.Specifically, the adapter 144 may be operatively coupled to a damperassembly and the damper access duct section 142 may be coupled to theadapter 144 with clamps 146, 148.

With reference to FIG. 12, in the embodiment shown, the damper accessduct section 142 has a sidewall 150 that defines a passage 152 along aninternal surface thereof. The damper access duct section 142 has atubular configuration and, in particular, has a rectangularcross-sectional configuration. In one embodiment, the cross-section ofthe duct section 142 is square. With regard to the rectangularconfiguration shown, the duct section 142 includes straight sides 154that join at corner regions 156. It will be appreciated, however, thatthe duct section 142 may have other cross-sectional shapes, includingfor example, elliptical or oval cross-sectional shapes (as shown inFIGS. 20A and 21A). Although not shown, the duct section 142 may includea liner, such as, internal insulation, along the internal surface of thesidewall 150. Similarly, the external surface of the sidewall 150 may becovered by an external liner (not shown), such as, external insulation.

With continued reference to FIG. 12, the sidewall 150 of the damperaccess duct section 142 has ends 158, 160 in which each end has or isprovided with a respective radially outwardly directed flange 162, 164.In one embodiment, one or both of the radially outwardly directedflanges 162, 164 are integrally formed with the sidewall 150, whichconfiguration may be achieved by folding tabs (not shown) relative tothe sidewall 150. The tabs (not shown) may be folded or bent asdescribed in greater detail below to form the flanges 162, 164.

In addition, and with reference to FIGS. 12 and 15A, one or both of theflanges 162, 164 may include a leg 166 extending generally transverse tothe radially outwardly directed portion of the respective flanges 162,164. By way of example and without limitation, each leg 166 may extendsubstantially perpendicular to the radial outwardly extending portion ofthe respective flanges 162, 164. As shown, each leg 166 may extendgenerally parallel to the longitudinal axis of the duct section 142. Itwill be appreciated that each leg 166 may extend the full perimeter ofthe radially outwardly extending portion of the flanges 162, 164. In theembodiment shown, each flange 162 and 164 includes multiplecircumferentially spaced-apart legs 166 around the perimeter of thesidewall 150. Spaced-apart legs 166 may correspond to the straight sides154 of the sidewall 150. As with the formation of the flanges 162, 164,the leg 166 may be integrally formed by folding a portion of the flange162, 164 toward the sidewall 150 so as to form a C-shape.

In one embodiment, and with reference to FIG. 12, a plurality of flanges162 may be formed by folding a corresponding tab (not shown) integrallyformed with the sidewall 150. Once the flanges 162 are formed, cornerreinforcement members 167 may be secured to adjacent flanges 162 by spotwelding or other means, such that, collectively, the cornerreinforcement members 167 and flanges 162 extend the full perimeter ofthe sidewall 150. Although not shown, it will be appreciated that thecorner reinforcement members 167 may be secured to adjacent flanges 164at end 160 of the duct section 142. Furthermore, the cornerreinforcement members 167 may be selectively secured to adjacent flanges162, 164. In other words, all corner regions 156 need not be reinforcedwith members 167.

Similar to the adapter 46 shown in FIG. 1, and with reference to FIGS.12 and 15, the adapter 144 includes a sidewall 170 that defines apassage 172. The sidewall 170 has ends 174 and 176. At least one of theends 174, 176 has a radially outwardly directed flange 178. The flange178 may be formed by methods described herein. For example, the flange178 may be formed by folding a tab (not shown) perpendicular to thesidewall 170 and thus may be similar to the flanges 162, 164 of the ductsection 142 in that regard. The adapter 144 has a rectangularconfiguration, which may be similar to the rectangular configuration ofthe duct section 142. In one embodiment, the adapter 144 has a squarecross-sectional shape, though other shapes are contemplated. Further, itwill be appreciated that embodiments of the invention are not limited tothe adapter 144 and the duct section 142 having the same shapeconfiguration.

Additionally, the flange 178 may include a leg 180 extending generallytransverse to the radially outwardly extending portion of the flange178. In one embodiment, each leg 180 extends at a perpendicular angle tothe radially outwardly extending portion of the flange 178 and may besimilar to the leg 166 described above. In this regard, each leg 180 mayextend generally parallel to the longitudinal axis of the adapter 144.Each leg 180 may be formed by folding a portion of the flange 178 towardthe sidewall 170 to form a C-shape. Alternatively, in embodiments inwhich one or more corner regions 179 are closed, that is, where the leg180 is continuous around the circumference of the flange 178, one orboth of the flange 178 and leg 180 may be separately formed in afaceplate and then the faceplate may be secured to the adapter 144, asis described in detail below.

In one embodiment, and with reference to FIGS. 11, 12, and 15, duringinstallation, the flanges 162 on the end 158 of the duct section 142 mayalign with the flange 178 on the end 174 of the adapter 144 in a directabutting relationship. That is, an outwardly facing surface of flange162 and an outwardly facing surface of flange 178 may be in contact withone another. With reference to FIG. 15, the flange 178 in combinationwith the flange 162, including integrally formed legs 166, 180 forms agenerally T-shaped joint 181. The clamp 146 may then be disposed overthe T-shaped joint 181 so as to operatively couple the damper accessduct section 142 to the adapter 144 and prevent unintentional separationthereof.

With reference now to FIGS. 12 and 13A, in one embodiment, the clamp 146includes a base portion 182 that generally defines an annular peripheryof the clamp 146. As shown, the periphery may include a rectangularshaped periphery, more particularly for example, a square shapedperiphery. However, it will be appreciated that the particular shape ofthe periphery is not limited to a rectangular one. For example, and withreference to FIGS. 14A, 14B, and 14C, a base portion may define anelliptical or oval shaped periphery.

The clamp 146 is configured to be placed at a joint between the flanges162 and 178. To that end, the base portion 182 may have ends 184 and186. The base portion 182 may have a length that is greater than theperimeter of the clamp 146 when it is closed. As shown in FIG. 13A, thebase portion 182 may be overlapped onto itself to form an overlap region188 between the ends 184 and 186.

In FIG. 12, the ends 184 and 186 may be separated and, although notshown, the separation of the ends 184 and 186 may be sufficient topermit installation of the clamp 146 around the joint formed by abutmentof the flange 162 to the flange 178. Once the clamp 146 is installed,the ends 184 and 186 may be brought in proximity to one another andsecured, for example, by a latch 189.

In operation, the clamp 146 has opened and closed positions that may bedefined by the relative positions of the ends 184 and 186. The openedposition permits the clamp 146 to be installed or removed from a joint.When the clamp 146 is closed, it is configured to secure two separateportions of the duct together. By way of example, clamp 146 mayremovably secure the duct section 142 to the adapter 144. The clamps146, 148 are in the closed positions in FIG. 11.

With reference to FIG. 13A, in one embodiment, the clamp 146 may furtherinclude lateral portions 190 and 192 that extend generally radiallyinward from the base portion 182. The lateral portions 190 and 192 mayconfront one another to define a channel 194 therebetween. In oneembodiment of the invention, a gasket member 196 is situated in thechannel 194. In FIG. 15, the channel 194 of the clamp 146 cooperateswith each leg 166, 180 of the joint 181 to removably secure the adapter144 to the duct section 142. As shown, the gasket member 196 is enclosedby the base portion 182; the lateral portions 190, 192; and the legs166, 180 and thus forms a fluid-tight seal at the T-shaped joint 181.

With reference to FIG. 13A, the lateral portions 190, 192 may not extendthe full length of the perimeter of the base portion 182. In otherwords, lateral portions 190, 192 may be discontinuous around theperimeter of the clamp 146. In this configuration, the clamp 146 mayinclude a plurality of lateral portions 190, 192 extending from selectedregions of the base portion 182. Where there are multiple lateralportions 190, 192 extending radially inward from the base portion 182,the lateral portions 190, 192 may be spaced apart at equal intervalsaround the circumference of the base portion 182 and be separated byopen regions 197 that may be formed by only the base portion 182. Itwill be appreciated that open regions 197 may facilitate installation ofthe clamp 146 onto the duct as they may increase the flexibility of thebase portion 182 in these areas that allows the ends 184 and 186 to befurther separated.

The number of lateral portions 190, 192 spaced apart along thecircumference of the clamp 146 may be determined in part by theconfiguration of the joint. In particular, the shape of the duct section142 and/or the adapter 144 may, in part, determine the number andlocation of the lateral portions 190, 192. The number of lateralportions 190, 192 may correspond to the number of flat sides of the ductto which the clamp 146 is to be attached. By way of example only andwith reference to FIG. 12, where the sidewall 150 generally defines arectangular cross-sectional configuration having four straight sides 154joined together at four corner regions 156, the clamp 146 may includefour spaced-apart lateral portions 190 and four spaced-apart lateralportions 192 each separated by base portion only or open regions 197.The configuration of the adapter 144 and/or the duct 12 may also bepartly determinative of the number and location of the lateral portions190, 192 on the clamp 146. It will be appreciated that embodiments ofthe present invention are not limited to the lateral portions 190, 192shown in FIG. 12. For example, the spaced apart lateral portions 190 andspaced apart lateral portions 192 may not be coextensive in number orcoextensive in length.

With reference to FIG. 13B, in another embodiment, a clamp 198 includesdiscrete members 200, 202 and 204. Selected pairs of members 200, 202,and 204 are operatively coupled together to allow relative movementbetween the selected member pairs. In particular, the members 200 and202 may be joined by a hinge 206 so that the members 200, 202 may bemoved relative (shown by arrow 208) to one another around the hinge 206during the installation and removal of the clamp 198 from a joint.Similarly, a hinge 210 operatively connects the members 202 and 204allowing relative movement (shown by arrow 212) between members 202 and204 during installation and removal of the clamp 198 from a joint.Relative movement between the members 200, 202, and 204 at thecorresponding hinges 206 and 210 allows sufficient separation of theends 184 and 186 so that the clamp 198 may be installed or removed froma joint.

In addition, each of the members 200, 202, and 204 includes acorresponding base portion 214, 216, and 218 that collectively definesthe annular periphery of the clamp 198. Similar to the clamp 146, shownin FIG. 13A, the base portions 214, 216, and 218 include lateralportions 220 and 222 that generally extend radially inward from thecorresponding base portion. Unlike the clamp 146, however, when theclamp 198 is closed, the respective lateral portions 220, 222 extendsubstantially along the entire periphery of the clamp 198. In otherwords, the collective lateral portions 220 and 222 are continuous aroundthe circumference of the clamp 198 along each base portion 214, 216, and218. The corner regions 224 are therefore closed. Even though the cornerregions 224 are closed, the clamp 198 may be opened via hinges 206, 210for installation and removal.

As shown in FIGS. 13A and 13B, the respective clamps 146, 198 may have arectangular configuration that generally corresponds to thecross-sectional configuration of the duct 12, as well as, thecross-sectional configurations of each of the duct section 142 andadapter 144. It will be appreciated that embodiments of the clamp asdescribed herein are not limited to a rectangular configuration. By wayof additional example and with reference to FIG. 14A, a clamp 230 has anelliptical configuration. As shown in FIG. 14A, the base portion 182defines the annular periphery of the clamp 230. The lateral portions190, 192 extend over only a limited length of the base portion 182. Byway of example only, the lateral portions 190, 192 generally correspondto regions along the corresponding duct that are flat or straight. Thebase portion only or open regions 197 separate the spaced-apart lateralportions 190, 192 and generally correspond to regions of thecorresponding duct that are curved. For example, curved regions mayinclude regions between the straight sides 154. With reference to FIG.12, the open regions 197 may correspond to the corner regions 156. Inthe context of an elliptical duct, as described below, the open regions197 may correspond to the curved regions between the straight or flatsides. It will be appreciated, however, that lateral portions 190, 192may extend over substantially all of or a portion of the curved area ofthe base portion 182.

Another embodiment of an elliptical clamp is shown in FIG. 14B. Inparticular, a clamp 232 has a similar elliptical configuration as theclamp 230 (FIG. 14A) though it includes hinges 206 and 210. The members200, 202, and 204 of the clamp 232 are thus movable relative to oneanother about hinges 206 and 210. The lateral portions 220 and 222extend substantially the entire perimeter of the clamp when the clamp232 is closed. In other words, the lateral portions 220 and 222 extendthe full length of the corresponding base portions 214, 216, and 218,including the curved portions of the members 200, 202, and 204. It willbe appreciated that lateral portions 220 and/or 222 may not extend thefull length of the corresponding base portions 214, 216, and 218. Inthis regard, as shown in FIG. 14C, the lateral portions 220 and/or 222are circumferentially spaced-apart along each of the base portions 214,216, and 218. While the clamp 232 in FIG. 14C is shown with hinges 206and 210, the clamp 232 may include one of the hinges 206 or 210.Alternatively, the clamp 232 in FIG. 14C may not include any hinges.

In addition, and with reference to FIGS. 13A, 13B, 14A, 14B, 14C and 15,any single one of the clamps 146, 198, 230, and 232 may further includea longitudinal extension 234 from the corresponding lateral portion 190,220 and a longitudinal extension 236 from the lateral portion 192, 222.The longitudinal extensions 234, 236 generally extend parallel to thelongitudinal axis of the respective duct section 142 or adapter 144, asis shown best in FIG. 15. It is believed that the longitudinalextensions 234, 236 increase the rigidity of the joint formed with theclamp.

In one embodiment of the invention shown in FIG. 12, the damper accessassembly 140 includes one or more faceplates 240. As will be describedin detail below, the faceplates 240 may facilitate assembly of thedamper access assembly 140 to an existing duct and/or facilitateassembly of the duct section 142 and the adapter 144.

FIGS. 12 and 16A depict a situation where the faceplate 240 may beattached to the duct 12 and/or the faceplate 240 may be attached to theadapter 144. Thus, the faceplate 240 may be installed onto existing ductwork that is being retrofitted to incorporate the duct access assembly140 or into a new installation. As shown in FIG. 12, the duct 12 mayinclude a radially outwardly extending flange 242. However, the flange242 may lack sufficient structure to which one of the clamps, asdescribed herein, may be secured to removably secure the damper accessduct section 142 to the duct 12. The faceplate 240 may be initiallysecured to the duct 12 prior to installation of the damper accessassembly 140 to improve the mechanical stability of the joint formedbetween the duct 12 and the duct section 142.

To that end, and with reference to FIGS. 12 and 16A, the faceplate 240may be spot welded or secured by other methods known in the art to theflange 242 of the duct 12 as shown at 244 (FIG. 16A). The faceplate 240includes a first leg 246 and a second leg 248. The first leg 246 isgenerally configured to abut an outwardly facing surface of the flange242 of the duct 12. The second leg 248 extends from the first leg 246 atan angle and may be generally perpendicular thereto. The faceplates 240may be made by folding a flat pattern (not shown) to form each of legs246, 248. Alternatively, the faceplates 240 may be stamped from a sheetof material.

As shown, a plurality of legs 248 may be spaced apart along theperiphery edge of the first leg 246. The spaced-apart legs 248 may becircumferentially separated by regions of the first leg 246. Thelocations of the spaced-apart legs 248 may be related to theconfiguration of the duct to which the faceplate 240 is to be attached.For example, where the duct section 142 has a rectangular configuration,as shown, the legs 248 may be positioned around the periphery of thefirst leg 246 and correspond to the sides 154 of the duct section 142.The regions of only the first leg 246 may correspond to the cornerregions 156 of the duct section 142 that join the straight sides 154. Itwill be appreciated that embodiments of the invention are not limited toany particular method of folding or stamping the faceplates 240described herein.

As shown in FIG. 16A, the faceplate 240 in combination with the flange164, including integrally formed leg 166, forms a generally T-shapedjoint 252. The channel 194 of the clamp 146 cooperates with each leg166, 248 to removably secure the duct 12 to the duct section 142. Asshown, the gasket member 196 is enclosed by the base portion 182; thelateral portions 190, 192; and the legs 166, 248 and thus forms afluid-tight seal at the T-shaped joint 252.

In one embodiment and with reference to FIG. 16B, the duct 12 may notinclude the flange 242, shown in FIG. 16A. In the absence of the flange242 to which the faceplate 240 is attached, the faceplate 240 mayinclude a third leg 254 that extends generally perpendicularly to thefirst leg 246. The third leg 254 may be butted against and then securedto the sidewall of the duct 12, via the spot weld 244, as shown. It willbe appreciated that the third leg 254 may be secured to the exterior ofthe duct 12 rather than the interior of the duct 12, as shown.

The faceplate 240 is not limited solely to attachment to the duct 12. Inthis regard and with reference to FIGS. 17A-17F, combinations of thefaceplates 240 may be arranged to form the T-shaped joint 181 betweenthe duct section 142 and the adapter 144 and/or the T-shaped joint 252between the duct 12 and the duct section 142.

For example, and with reference specifically to FIG. 17A, a pair offaceplates 240 may be individually secured to each of the duct section142, which does not include the leg 180, and the duct 12. Because eachof the section 142 and the duct 12 lacks any leg extending substantiallyparallel to the longitudinal axis of the duct, the faceplates 240 may beattached thereto so as to form the T-shaped joint 252. Additionally, thefaceplate 240 may further include the third leg 254 extending at atransverse angle from the first leg 246 generally in the same directionas the second leg 248 thereby forming a generally C-shaped crosssection.

As shown in FIG. 17A, the third leg 254 may cooperate with the interiorsurface of the sidewall 150 of the duct section 142. This configurationmay advantageously facilitate installation of the faceplate 240 onto therespective duct portion. The faceplate 240 may remain in place longenough that it may be secured thereto in a subsequent operation (forexample, by spot welding). And, with reference to FIG. 17B, the firstleg 246 of the faceplate 240 may be extended with the third leg 254oriented to cooperate with any insulation or lining 256 on the interiorsurface of the respective duct portion.

With reference to FIG. 17C, the T-shaped joint 181 is formed by thecombination of leg 166 and leg 180, though the joint differs in that thegasket member 196 is sandwiched between the flanges 162 and 178. Inaddition, the faceplate 240 forms the flange 178 and the leg 180. Thefaceplate 240 is secured to the adapter 144, as described above. FIGS.17D-17F depict additional embodiments in which the faceplate 240 issecured to the duct 12 and/or the duct section 142, however, the gasketmember 196 is sandwiched between the opposing faceplates 240 rather thanbetween the base portion and the legs.

In one embodiment of the invention depicted in FIGS. 18 and 19, theclamp 146 further includes a dimple or restriction element 260 thatprojects into the channel 194 from one or both lateral portions 190,192. As shown, multiple dimples 260 may directly oppose one another.However, embodiments of the invention are not limited to theconfiguration shown. The dimples 260 may be offset from one anotheracross the channel 194 or the dimples 260 may extend only from thelateral portion 190 or from the lateral portion 192, but not both.Advantageously, the dimples 260 may improve the structural integrity ofthe joint 181, 252 by contacting the faceplate 240. In particular, thedimple 260 may include a flat surface which supports or contacts thesecond leg 248 of the faceplate 240 thereby further restricting relativemotion between the clamp 146 and the faceplate 240. In other words, thedimples 260 inhibit movement of the clamp 146 away from the T-shapedjoint 181, 252.

As set out above and with reference now to FIG. 20A, in one embodimentof the invention, a damper access duct section 280 has a sidewall 282that defines a passage 284 along an internal surface thereof. Thesection 280 is similar to the damper access duct section 142 describedabove and shown in FIG. 12 though the duct section 280 differs incross-sectional configuration. As shown, the duct section 280 is ovalshaped but is similar to the duct section 142 in other respects.Nevertheless, the duct section 280 will be briefly described.

The damper access duct section 280 has a tubular configuration and, inparticular, has an oval cross-sectional configuration. With regard tothe oval configuration shown, the duct section 280 includes straightsides 286 that are connected by curved sides 288. It will be appreciatedthat the sides 286 may be much longer or shorter than those shown, thatis, oval configurations of the duct section 280 are not restricted tothe specific cross-sectional shape shown. In addition, the duct section280 may include a liner, such as, internal insulation, along the passage284. Similarly, the external surface of the sidewall 280 may be coveredby an external liner (not shown), such as, external insulation.

The sidewall 282 of the damper access duct section 280 has at least oneend 290. In addition, in one embodiment, a faceplate 300 may be securedto end 290 of the duct section 280 similar to the faceplate 240 set outabove. As shown, the faceplate 300 may include a flange 302 and one ormore legs 304. A second leg 306 may generally extend in the samedirection from the flange 302 as the leg 304. Legs 304, 306 may besimilar to legs 248, 254, respectively, in that regard. Further, thefaceplate 300 may be made according to similar methods disclosed abovewith regard to folding or stamping the faceplate 240. As shown, the legs304, 306 may configured to extend continuously around the perimeter ofthe flange 302 so as to encompass the entire end 290 of the duct section280 when the faceplate 300 is assembled on the section 280.

In the embodiment shown in FIGS. 20A and 20B, in which the duct section280 lacks an outwardly-directed flange, the faceplate 300 may beattached to the duct section 280 along the sidewall 282. For example,the faceplate 300 may be spot welded to the duct section 280 at 244within the passage 284 (FIG. 20B). The leg 306 may extend along theinterior of the sidewall 282 with the leg 304 being provided externallyto form a joint with another duct section and secured with a clamp, suchas, the clamp 230 (FIG. 14A) or the clamp 232 (FIGS. 14B and 14C).

In one embodiment, shown in FIGS. 21A and 21B, the duct section 280 mayinclude a radially outwardly directed flange 292 at end 290. Forexample, the flange 292 may be provided only along selected portions ofthe duct section 280, such as the straight sides 286 thereof. In oneembodiment, the faceplate 300 may include legs 304 and 306 extendingfrom the flange 302 only along selected portions thereof, such as thestraight portions thereof, as shown, which may correspond in location tothe sides 286. Regions of only the leg 302 may correspond to the curvedsides 288 or to those regions between the straight sides 286 of the duct280. The faceplate 300 may be secured to the flange 292, similar to thefaceplate 240 as set out above, by spot welds at 244. Once the faceplate300 is attached to the duct section 280, the legs 304, 306 cooperatewith the duct section 280. The faceplate 300 is configured to form ajoint with an adjacent ductwork or adapter similar to the faceplate 240and secured with a clamp, such as, the clamp 230 (FIG. 14A) or the clamp232 (FIGS. 14B and 14C).

While the present invention has been illustrated by description ofvarious embodiments and while those embodiments have been described inconsiderable detail, it is not the intention of applicants to restrictor in any way limit the scope of the appended claims to such details.Additional advantages and modifications will readily appear to thoseskilled in the art. The invention in its broader aspects is thereforenot limited to the specific details and illustrative examples shown anddescribed. Accordingly, departures may be made from such details withoutdeparting from the spirit or scope of applicants' invention.

Having described the invention, what is claimed is:
 1. A clamp assemblyfor joining a first outwardly directed flange of a first duct with asecond outwardly directed flange of a second duct, the outwardlydirected flanges being configured to confront one another and define agap therebetween to form a joint, the assembly comprising: acircumferential clamp member including a base portion defining anannular periphery of the member and first lateral portions and secondlateral portions each extending inwardly from the base portion to definea channel therebetween for receiving the first and second flanges, thefirst lateral portions and second lateral portions includinglongitudinal extensions that extend away from the channel to increaserigidity of the joint, wherein each of the first outwardly directedflange and the second outwardly directed flange includes a leg extendingtransversely therefrom, the transverse legs being configured to form agenerally T-shaped joint when the first flange confronts the secondflange, wherein the channel of the clamp member is configured to receivethe T-shaped joint therein.
 2. The clamp assembly of claim 1, whereinthe first lateral portions include a plurality of circumferentiallyspaced-apart first lateral portions and the second lateral portionsinclude a plurality of circumferentially spaced-apart second lateralportions.
 3. The clamp assembly of claim 2, wherein the duct includes aplurality of straight sides and wherein the number of spaced-apart firstlateral portions and the number of spaced-apart second lateral portionscorrespond to the number of straight sides of the first and secondducts.
 4. The clamp assembly of claim 2, wherein the spaced-apart firstlateral portions and the spaced-apart second lateral portions arecircumferentially separated by base-portion-only regions.
 5. The clampassembly of claim 4, wherein the base-portion-only regions of the clampmember correspond to regions between the straight sides of the first andsecond ducts.
 6. The clamp assembly of claim 1, wherein each of thefirst and second lateral portions is discontinuous at one region alongthe circumferential length of the clamp member.
 7. The clamp assembly ofclaim 1, further comprising: at least one faceplate configured to besecured to one of the first duct or the second duct, the faceplateincluding a first leg and a second leg extending at an angle transverseto the first leg, wherein the clamp member is configured to receive atleast one of the first leg or the second leg therein.
 8. The clampassembly of claim 7, wherein each of the first duct and the second ductincludes a sidewall, and wherein the faceplate further includes a thirdleg configured to cooperate with the sidewall of one of the first ductsection or the second duct section.
 9. The clamp assembly of claim 1,further comprising: a first faceplate configured to be secured to thefirst duct and a second faceplate configured to be secured to the secondduct, the first and second faceplates each including a first legconfigured to be secured to a respective duct and a second leg orientedat a transverse angle relative to the first leg, and, when secured tothe corresponding duct, the first and second faceplates are configuredto form a generally T-shaped joint between the first and second ducts,wherein the channel is configured to receive the T-shaped joint therein.10. The clamp assembly of claim 9, wherein the first legs of each of thefaceplates extend along the entire periphery of the respective duct andthe second legs of one or both of the first and second faceplates arediscontinuous along the periphery of the respective duct so as to formspaced-apart first-leg-only regions.
 11. The clamp assembly of claim 10,wherein one of the first duct or the second duct includes a plurality ofspaced-apart straight sides and wherein the first-leg-only regionscorrespond to regions of the duct between the spaced-apart straightsides.
 12. A clamp assembly for joining a first outwardly directedflange of a first duct with a second outwardly directed flange of asecond duct, the flanges being configured to confront one another anddefine a gap therebetween to form a joint, the assembly comprising: afirst member; a second member; and a hinge operatively coupling thefirst clamp member to the second clamp member to form at least a portionof a circumferential clamp member, the first member being moveablerelative to the second member by the hinge between an opened position inwhich the clamp member is installable onto the first and second ductsand a closed position in which the assembly engages each of the firstand second flanges, wherein each of the first and second membersincludes a base portion, a first lateral portion, and a second lateralportion, the first lateral portion and the second lateral portion eachextend inwardly from the base portion to define a channel therebetweenfor receiving the first and second flanges, the first lateral portionsand the second lateral portions including longitudinal extensions thatextend away from the channel to increase rigidity of the joint, andwherein each of the first outwardly directed flange and the secondoutwardly directed flange includes a leg extending transverselytherefrom, the transverse legs being configured to form a generallyT-shaped joint when the first flange confronts the second flange,wherein the channel of the clamp member is configured to receive theT-shaped joint therein.
 13. The clamp assembly of claim 12 furthercomprising: at least one faceplate configured to be secured to at leastone of the first or the second ducts, the faceplate including a firstleg configured to be secured to the duct section and a second legoriented at a transverse angle with respect to the first leg, whereinthe clamp member is configured to receive the faceplate therein.
 14. Theclamp assembly of claim 12 further comprising: a first faceplateconfigured to be secured to the first duct and a second faceplateconfigured to be secured to the second duct, the first and secondfaceplates each including a first leg configured to be secured to arespective duct and a second leg oriented at a transverse angle withrespect to the first leg, the first and second faceplates beingconfigured to form a generally T-shaped joint between the first andsecond ducts, wherein the channel of the clamp member is configured toreceive the T-shaped joint therein.
 15. The clamp assembly of claim 14,wherein the first legs of each of the faceplates extend along the entireperiphery of the respective duct and the second legs of one or both ofthe first and second faceplates are discontinuous along the periphery ofthe respective duct so as to form spaced-apart first-leg-only regions.16. The clamp assembly of claim 15, wherein the first and second ductshave a plurality of spaced-apart straight sides and wherein thefirst-leg-only regions correspond to regions of the respective ductbetween the spaced-apart straight sides.
 17. A damper access assemblyfor use in a ventilation duct system including ductwork and a damperenclosure configured to enclose a damper and having an inlet and anoutlet operatively coupled to the ductwork, the damper access assemblycomprising: an adapter defining a passage therethrough and having afirst end and a second end, the first end sized to fit over or fitwithin one of the inlet or outlet of the damper enclosure and the secondend including a first radially outwardly directed flange including a legextending at a transverse angle therefrom; and a damper access ductsection defining a passage therethrough and having a first end and asecond end, each of the first end and the second end of the damperaccess duct section including a second radially outwardly directedflange at the respective first end and second end thereof, each of thesecond flanges including a leg extending at a transverse angletherefrom, the first and one of the second flanges being configured toform a generally T-shaped joint between the adapter and the damperaccess duct section; and a circumferential clamp member including a baseportion that defines an annular periphery of the clamp member andincluding first lateral portions and second lateral portions that eachextend inwardly from the base portion to define a channel therebetweenfor receiving the generally T-shaped joint to releasably couple thedamper access duct section to the adapter, the first lateral portionsand the second lateral portions including longitudinal extensions thatextend away from the channel to increase rigidity of the joint, whereinthe circumferential clamp member is configured to operatively andreleasably couple the damper access duct section to the adapter at theT-shaped joint so that the damper access duct section is removablerelative to the damper enclosure and the ductwork to permit access tothe damper when the damper access duct section is removed.
 18. Thedamper access assembly of claim 17 further comprising: a faceplateconfigured to be secured to the ductwork, the faceplate including afirst leg configured to be secured to the ductwork and a second legoriented at a transverse angle with respect to the first leg, the secondleg of the faceplate and the second leg of the duct section beingconfigured to form a generally T-shaped joint between the ductwork andthe damper access duct section.
 19. The damper access assembly of claim18, further comprising: a second circumferential clamp member includinga base portion that defines an annular periphery of the clamp member andincluding first lateral portions and second lateral portions that eachextend inwardly from the base portion, the first lateral portions beinggenerally parallel to the second lateral portions to define a channeltherebetween for receiving the generally T-shaped joint formed by thefaceplate and the second flange on the damper access duct section toreleasably couple the damper access duct section to the ductwork, andthe first lateral portions and the second lateral portions includinglongitudinal extensions that extend away from the channel to increaserigidity of the joint.
 20. A damper access assembly for use in aventilation duct system including ductwork and a damper enclosureconfigured to enclose a damper and having an inlet and an outletoperatively coupled to the ductwork, the damper access assemblycomprising: an adapter defining a passage therethrough and having afirst end and a second end, the first end being sized to fit over or fitwithin one of the inlet or outlet of the damper enclosure and the secondend including a first radially outwardly directed flange including a legextending at a transverse angle therefrom; and a damper access ductsection defining a passage therethrough and having a first end and asecond end, each of the first end and the second end of the damperaccess duct section including a second radially outwardly directedflange at the respective first end and second end thereof, each of thesecond flanges including a leg extending at a transverse angletherefrom, the first and one of the second flanges being configured toform a generally T-shaped joint between the adapter and the damperaccess duct section; and a circumferential clamp member including afirst member, a second member, and a hinge operatively coupling thefirst member to the second member, the first member being moveablerelative to the second member by the hinge between an opened position inwhich the clamp member is installable onto the first and second flangesand a closed position in which the annular clamp member engages each ofthe first and second flanges to releasably couple the access ductsection to the adapter, each of the first and second members including abase portion defining an annular periphery of the clamp member and afirst lateral portion and a second lateral portion each extendinginwardly from the base portion to define a channel therebetween forreceiving the generally T-shaped joint, and the first lateral portionsand the second lateral portions including longitudinal extensions thatextend away from the channel to increase rigidity of the joint, whereinthe circumferential clamp member is configured to operatively andreleasably couple the damper access duct section to the adapter at theT-shaped joint so that the damper access duct section is removablerelative to the damper enclosure and the ductwork to permit access tothe damper when the damper access duct section is removed.
 21. Thedamper access assembly of claim 20 further comprising: a faceplateconfigured to be secured to the ductwork, the faceplate including afirst leg and a second leg oriented at a transverse angle with respectto the first leg, the first and second faceplates being configured toform a generally T-shaped joint between the ductwork and the damperaccess duct section.
 22. The damper access assembly of claim 21, furthercomprising: a second circumferential clamp member including a firstmember, a second member and a hinge operatively coupling the firstmember to the second member, each of the first and second membersincluding a base portion defining an annular periphery of the clampmember and a first lateral portion and a second lateral portion eachextending inwardly from the base portion, the first lateral portionbeing generally parallel to the second lateral portion to define achannel therebetween for receiving the generally T-shaped joint, thefirst lateral portions and the second lateral portions includinglongitudinal extensions that extend away from the channel to increaserigidity of the joint, and the first member being moveable relative tothe second member by the hinge between an opened position in which theclamp member is installable onto the generally T-shaped joint and aclosed position in which the annular clamp member engages the generallyT-shaped joint to releasably couple the access duct section to theductwork.